diff --git a/.github/workflows/import-smoke-on-ubuntu-py3-12.yml b/.github/workflows/import-smoke-on-ubuntu-py3-12.yml
deleted file mode 100644
index 35427cc..0000000
--- a/.github/workflows/import-smoke-on-ubuntu-py3-12.yml
+++ /dev/null
@@ -1,34 +0,0 @@
-name: import-smoke
-
-# Catches "wheel installs but `import scitex_stats` blows up at runtime"
-# — separate from the full pytest suite so a broken entry-point fails
-# fast without paying for the matrix. Companion to `tests` — confirms
-# the bare package (no extras) is `pip install -e .`-able and
-# `import scitex_stats` succeeds. Catches `[project] dependencies`
-# drift that the test matrix masks because it installs `[all,dev]`.
-
-on:
-  push:
-    branches: [main, develop]
-  pull_request:
-    branches: [main, develop]
-  schedule:
-    - cron: "0 7 * * *"  # nightly 07:00 UTC
-  workflow_dispatch:
-
-jobs:
-  install-check:
-    name: import-smoke-on-ubuntu-py3-12
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-python@v5
-        with:
-          python-version: "3.12"
-      - name: Install (no extras)
-        run: |
-          python -m venv .venv
-          .venv/bin/pip install --upgrade pip
-          .venv/bin/pip install -e .
-      - name: Import smoke
-        run: .venv/bin/python -c "import scitex_stats; print(scitex_stats.__version__)"
diff --git a/.github/workflows/pr-ci.yml b/.github/workflows/pr-ci.yml
new file mode 100644
index 0000000..8acb446
--- /dev/null
+++ b/.github/workflows/pr-ci.yml
@@ -0,0 +1,134 @@
+name: pr-ci
+
+# Consolidated PR-only CI gate. Runs the per-PR validation suite as a
+# single workflow so the cancel-in-progress concurrency group, path
+# filters, and uv cache apply uniformly. Post-merge validation lives
+# in release-ci.yml.
+#
+# L1 concurrency — cancel superseded PR runs.
+# L3 path filters — skip docs/skills/examples/markdown-only PRs.
+# L4 conditional matrix — full ["3.11", "3.12", "3.13"] on PR (this trigger).
+# L5a uv-managed Python (`uv python install` + `uv venv --python`) so the
+#     matrix leg is not bound to the runner's system Python.
+# L5b .venv/bin on PATH (and explicit `.venv/bin/python` for clarity) so
+#     console scripts resolve without needing `uv run`.
+
+on:
+  pull_request:
+    branches: [main, develop]
+    paths-ignore:
+      - 'docs/**'
+      - '_skills/**'
+      - 'examples/**'
+      - '**.md'
+      - 'CHANGELOG.*'
+      - '.github/CODEOWNERS'
+      - '.github/ISSUE_TEMPLATE/**'
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: ${{ github.event_name == 'pull_request' }}
+
+jobs:
+  import-smoke:
+    name: import-smoke-on-ubuntu-py3-12
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install uv
+        uses: astral-sh/setup-uv@v3
+        with:
+          enable-cache: true
+          cache-dependency-glob: pyproject.toml
+      - name: Set up Python 3.12 (uv-managed)
+        run: uv python install 3.12
+      - name: Install (no extras) in uv venv
+        run: |
+          uv venv --python 3.12 .venv
+          uv pip install --python .venv/bin/python -e .
+      - name: Import smoke
+        run: .venv/bin/python -c "import scitex_stats; print(getattr(scitex_stats, '__version__', 'unversioned'))"
+      - name: smoke scitex-stats --help
+        run: .venv/bin/scitex-stats --help
+  dep-hygiene-smoke:
+    name: dep-hygiene-smoke
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install uv
+        uses: astral-sh/setup-uv@v3
+        with:
+          enable-cache: true
+          cache-dependency-glob: pyproject.toml
+      - name: Set up Python 3.11 (uv-managed)
+        run: uv python install 3.11
+      - name: Bare install (no extras) in uv venv
+        run: |
+          uv venv --python 3.11 .venv
+          uv pip install --python .venv/bin/python .
+      - name: Import package
+        run: .venv/bin/python -c "import scitex_stats; print(scitex_stats.__name__)"
+
+  tests:
+    name: pytest-matrix-on-ubuntu-py${{ matrix.python-version }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ${{ github.event_name == 'pull_request' && fromJson('["3.11", "3.12", "3.13"]') || fromJson('["3.12"]') }}
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install uv
+        uses: astral-sh/setup-uv@v3
+        with:
+          enable-cache: true
+          cache-dependency-glob: pyproject.toml
+      - name: Set up Python ${{ matrix.python-version }} (uv-managed)
+        run: uv python install ${{ matrix.python-version }}
+      - name: Create uv venv on this matrix Python
+        run: uv venv --python ${{ matrix.python-version }} .venv
+      - name: Install dependencies
+        # Fallback chain: prefer [all,dev] so optional-dep code paths
+        # get exercised. Falls back to [dev] then plain editable so a
+        # packaging hiccup doesn't strand CI.
+        run: |
+          uv pip install --python .venv/bin/python -e ".[all,dev]" \
+            || uv pip install --python .venv/bin/python -e ".[dev]" \
+            || uv pip install --python .venv/bin/python -e .
+      - name: Run tests
+        # PATH prepend so any test that subprocess-calls a console script
+        # finds it in .venv/bin/.
+        run: |
+          export PATH="$PWD/.venv/bin:$PATH"
+          .venv/bin/pytest tests/ --cov=src/scitex_stats --cov-report=xml --cov-report=term
+      - name: Upload coverage to Codecov
+        if: always() && matrix.python-version == '3.12'
+        uses: codecov/codecov-action@v5
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          files: ./coverage.xml
+          fail_ci_if_error: false
+
+  audit:
+    name: audit
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install uv
+        uses: astral-sh/setup-uv@v3
+        with:
+          enable-cache: true
+          cache-dependency-glob: pyproject.toml
+      - name: Set up Python 3.12 (uv-managed)
+        run: uv python install 3.12
+      - name: Install package + audit tooling
+        run: |
+          uv venv --python 3.12 .venv
+          uv pip install --python .venv/bin/python -e ".[dev]"
+          uv pip install --python .venv/bin/python "scitex-dev[cli-audit]"
+      - name: Run scitex-dev ecosystem audit-all
+        run: |
+          export PATH="$PWD/.venv/bin:$PATH"
+          scitex-dev ecosystem audit-all scitex-stats --no-version-check
diff --git a/.github/workflows/pytest-matrix-on-ubuntu-py3-11-3-12-3-13.yml b/.github/workflows/pytest-matrix-on-ubuntu-py3-11-3-12-3-13.yml
deleted file mode 100644
index 99cef14..0000000
--- a/.github/workflows/pytest-matrix-on-ubuntu-py3-11-3-12-3-13.yml
+++ /dev/null
@@ -1,42 +0,0 @@
-name: tests
-
-on:
-  push:
-    branches: [main, develop]
-  pull_request:
-    branches: [main, develop]
-  schedule:
-    - cron: "0 7 * * *"  # nightly 07:00 UTC
-  workflow_dispatch:
-
-jobs:
-  test:
-    name: pytest-matrix-on-ubuntu-py${{ matrix.python-version }}
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        python-version: ["3.11", "3.12", "3.13"]
-    steps:
-      - uses: actions/checkout@v4
-      - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v5
-        with:
-          python-version: ${{ matrix.python-version }}
-      - name: Install dependencies
-        run: |
-          python -m pip install --upgrade pip
-          # Fallback chain: prefer [all,dev] so optional-dep code paths
-          # (yaml, fastmcp, textual) get exercised. Falls back to [dev] then
-          # plain editable so a packaging hiccup doesn't strand CI.
-          pip install -e ".[all,dev]" || pip install -e ".[dev]" || pip install -e .
-      - name: Run tests
-        run: |
-          pytest tests/ --cov=src/scitex_stats --cov-report=xml --cov-report=term
-      - name: Upload coverage to Codecov
-        if: always() && matrix.python-version == '3.12'
-        uses: codecov/codecov-action@v5
-        with:
-          token: ${{ secrets.CODECOV_TOKEN }}
-          files: ./coverage.xml
-          fail_ci_if_error: false
diff --git a/.github/workflows/release-ci.yml b/.github/workflows/release-ci.yml
new file mode 100644
index 0000000..7716c82
--- /dev/null
+++ b/.github/workflows/release-ci.yml
@@ -0,0 +1,100 @@
+name: release-ci
+
+# Post-merge validation gate. Runs on push to protected branches
+# (main, develop) and as the canonical scheduled run. Always uses the
+# FULL pytest matrix — no conditional skipping — so the protected-branch
+# history is exercised on every supported Python.
+#
+# L1 concurrency — coalesce overlapping pushes on the same branch.
+# L5a uv-managed Python (`uv python install` + `uv venv --python`) so each
+#     matrix leg pins its interpreter independently of the runner.
+# L5b .venv/bin on PATH so console scripts resolve without `uv run`.
+
+on:
+  push:
+    branches: [main, develop]
+  schedule:
+    - cron: "0 7 * * *"  # nightly 07:00 UTC
+  workflow_dispatch:
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: false
+
+jobs:
+  tests:
+    name: pytest-matrix-on-ubuntu-py${{ matrix.python-version }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.11", "3.12", "3.13"]
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install uv
+        uses: astral-sh/setup-uv@v3
+        with:
+          enable-cache: true
+          cache-dependency-glob: pyproject.toml
+      - name: Set up Python ${{ matrix.python-version }} (uv-managed)
+        run: uv python install ${{ matrix.python-version }}
+      - name: Create uv venv on this matrix Python
+        run: uv venv --python ${{ matrix.python-version }} .venv
+      - name: Install dependencies
+        run: |
+          uv pip install --python .venv/bin/python -e ".[all,dev]" \
+            || uv pip install --python .venv/bin/python -e ".[dev]" \
+            || uv pip install --python .venv/bin/python -e .
+      - name: Run tests
+        run: |
+          export PATH="$PWD/.venv/bin:$PATH"
+          .venv/bin/pytest tests/ --cov=src/scitex_stats --cov-report=xml --cov-report=term
+      - name: Upload coverage to Codecov
+        if: always() && matrix.python-version == '3.12'
+        uses: codecov/codecov-action@v5
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          files: ./coverage.xml
+          fail_ci_if_error: false
+
+  import-smoke:
+    name: import-smoke-on-ubuntu-py3-12
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install uv
+        uses: astral-sh/setup-uv@v3
+        with:
+          enable-cache: true
+          cache-dependency-glob: pyproject.toml
+      - name: Set up Python 3.12 (uv-managed)
+        run: uv python install 3.12
+      - name: Install (no extras) in uv venv
+        run: |
+          uv venv --python 3.12 .venv
+          uv pip install --python .venv/bin/python -e .
+      - name: Import smoke
+        run: .venv/bin/python -c "import scitex_stats; print(getattr(scitex_stats, '__version__', 'unversioned'))"
+
+  audit:
+    name: audit
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install uv
+        uses: astral-sh/setup-uv@v3
+        with:
+          enable-cache: true
+          cache-dependency-glob: pyproject.toml
+      - name: Set up Python 3.12 (uv-managed)
+        run: uv python install 3.12
+      - name: Install package + audit tooling
+        run: |
+          uv venv --python 3.12 .venv
+          uv pip install --python .venv/bin/python -e ".[dev]"
+          uv pip install --python .venv/bin/python "scitex-dev[cli-audit]"
+      - name: Run scitex-dev ecosystem audit-all
+        run: |
+          export PATH="$PWD/.venv/bin:$PATH"
+          scitex-dev ecosystem audit-all scitex-stats --no-version-check
diff --git a/.github/workflows/scitex-stats-quality-audit-on-ubuntu-latest.yml b/.github/workflows/scitex-stats-quality-audit-on-ubuntu-latest.yml
deleted file mode 100644
index 702dd53..0000000
--- a/.github/workflows/scitex-stats-quality-audit-on-ubuntu-latest.yml
+++ /dev/null
@@ -1,57 +0,0 @@
-name: quality
-
-# Single-package quality gate — runs `scitex-dev ecosystem audit-all`
-# against this package (audit-cli / audit-mcp-tools / audit-skills /
-# audit-python-apis / audit-project). Mirrors the canonical audit that
-# `tests/develop/test_audit.py` runs inside the test suite, but as a
-# standalone gate so an audit regression is visible even when the matrix
-# is skipped.
-#
-# The previous body of this workflow shallow-cloned the entire ecosystem
-# and ran `scripts/quality/audit_ecosystem.py` — both of which live only
-# in scitex-dev, not in leaf packages. That template was copied here
-# verbatim and was always broken (FileNotFoundError on a non-existent
-# ecosystem registry file). This version audits just this package.
-
-on:
-  schedule:
-    - cron: "0 8 * * *"  # 08:00 UTC, after the 07:00 per-repo Test runs
-  workflow_dispatch:
-  push:
-    branches: [develop]
-    paths:
-      - "src/**"
-      - "tests/**"
-      - "pyproject.toml"
-      - ".github/workflows/scitex-stats-quality-audit-on-ubuntu-latest.yml"
-  pull_request:
-    branches: [main, develop]
-
-jobs:
-  audit:
-    runs-on: ubuntu-latest
-    timeout-minutes: 20
-    steps:
-      - uses: actions/checkout@v4
-
-      - uses: actions/setup-python@v5
-        with:
-          python-version: "3.12"
-
-      - name: Install package + audit tooling
-        run: |
-          python -m pip install --upgrade pip
-          pip install -e ".[dev]"
-          pip install "scitex-dev[cli-audit]"
-
-      - name: Run scitex-dev ecosystem audit-all
-        # warn-only: scitex-stats has a 1917-violation backlog (mostly
-        # PA-307 §3 test-quality on tests/examples/*), tracked in a
-        # follow-up issue (linked from this PR). The findings still
-        # surface in this step's logs so they're discoverable; we just
-        # don't fail the workflow on them — the goal is to stop the
-        # nightly cron from emailing the operator about a backlog the
-        # template swap itself didn't introduce. Drop `continue-on-error`
-        # once the backlog is under the audit-all threshold.
-        continue-on-error: true
-        run: scitex-dev ecosystem audit-all scitex-stats --no-version-check